Method of utilizing radiant energy.



45s-519 nu 233 Ex x f i\ Frpfgo 0R 685,958

No. Gamesa. Patentd nov. 5, Ism.

, u. TEsLA.

METHUD 0F UTILIZING RADIANT ENERGY.

(Appnmion mea 1m. 21, 1901. (No Model.)

Minnnngsmcvfmmomwmmomna L l PATENT OFFICE. i

NIKOLA TESLA, OF NEW YORK, N. Y.

YVMETHOD OF UTILI-ZING RADIANT ENERGY.

SPECIFICATION forming part of Letters Patent N o. 685,958, dated November 5, 1901. Application iiled March 21, 1901'. Serial No. 52,154. (No niodelaY g' To @ZZ whom it may concern:

Be it known that I, NIKOLA TESLA, a citizen of the United States, residing at the borough specification, reference being had to the drawings accompanying and forming a part of the same.

It is well known that certainradiationssuch as those of ultra-violet light, cathodic,

Roentgen rays, or the likes-possess the propf IS erty of charging and discharging conductors of electricity, the discharge being particularly noticeable when the conductor upon which the rays impinge is negatively electritied. These radiations are generally considered to be ether vibrations of extremelysmall wavelengths, and in explanation of the phenomena noted it has been assumed by some authorities that they ionize .or render conducting the atmosphere through which they are propagated. My own experiments and observations, however, lead me to conclusions more in accord with the theory heretofore advanced by me that sources of, such radiant energy throw oi with great velocity minute particles of matter which are strongly electrified, and therefore capable of charging an electrical conductor, or even if not so may at any rate discharge an electrified conductor either -by carrying oi bodilyits charge or otherwise.

My present application is based upon a discovery which I have made that when rays or radiations of the above kind are permitted to fall upon an insulated conducting body connected to one of the terminals of a condenser, while the other terminal of the same is made by independent means to receive or to carry away electricity, a current iiows into the condenser so long as the insulated body is' exposed to the rays, and under the conditions hereinafter specied au indefinite accumulation of electrical energy in the condenser takes place. This energy after a suitable timeinterval, during which the rays are allowed to act, may manifest itself in a powerful discharge, which may be utilized for the operation or control of mechanical or eleci trical devices or rendered useful in many other ways.

In applying my discovery I provide a condenser, preferably ofconsiderable electrostatic capacity, and connect one of its terminals to an insulated metal plate or other conducting body exposed to the rays -or streams of radiant matter. It is veryimportant,particularly in view of the fact fhatelectrical energy is generally supplied at a very slow rate to the condenser, to construct .the same with the greatest care. I use by preference the bestquality of mica as dielectric, taking every possible 'precaution in insulating the armatures, so that the instrument may withstand great electrical pressures without leaking and may leave no perceptible electriication when discharging instantaneously. In practice I have found that the best results are obtained with condensers treated in the manner described in a patent granted to me February 23, 1897, No. 577,671. Obviously the above precautions should be the more rigorously observed the slower the rate of charging and the smaller the time interval during which the energy is allowed to accumulate in the condenser. The insulated plate or conducting body should present as large a sur face as practicable to the rays or streams of matter, I having ascertained that the amount of energy conveyed to it per unit of time is under otherwise identical conditions proportionate to the area exposed,or nearly so. Furthermore, the surface should be clean and preferably highly polished or amalgamated. The second terminal or armature ot' the condenser may be connected to one of the poles of a battery or othes source of electricity or to any conducting body or object whatever of ,such properties or so conditioned that by its means electricity of the required sign will be supplied to the terminal. A simple way of supplying positive or negative electricity toy the terminal is to connect the same either to4 an insulated conductor, supported at some height in the atmosphere, or to a grounded conductor, the former, as is wellknown, furnishing positive and the latter negative electricity. As the rays or supposed streams of matter generally convey a positive charge to the tirst condenser-terminal,which is connectfss ed to the plate' or conductor above mentioned, I usually connect the second terminal of the condenser to the ground, this being the most convenient Way of obtainin g negative electricity, dispensing with the necessity of providing au artificial source. In order to utilize for any useful purpose the energy accumulated in the condenser, I furthermore connect to the terminals of the same a circuit including an instrument or apparatus which it is desired to operate and another instrument or device for alternately closing and opening the circuit. This latter maybe any form ofcircuit-controller, with fixed or movable partsY or electrodes, which may be actuated either by the stored energy or byindependent means.

The rays or radiations which are to be ntilized for the operation of the apparatus above described in general terms may be derived from a natural source, as the sun, or may be artificially produced by such means, for example, as an arc-lamp, a Roentgen tube, and the like, yand they may be employed for a great variety of useful purposes.

My discovery will be more f ully understood 'from the following detailed description and annexed drawings, to which reference is now made', and in which- Figure 1 is adiagram showing typical forms of the devices or elements as arranged and connected in applying the method for the operation of a-mechanical coutrivance or instrumentsolely by the'energy stored; and Fig. 2 is a diagram matical representation of a modied arrangement suitable for special purposes, with a circuit-controller actuated by independent means.

`Referring to Fig. l, O is the condenser, P the insulated plate or conducting bod y,which isexposed to the rays, and P another plate-or conductor, all being joined in series,as shown. The terminals T T of the condenser are also connected to a circuit including a receiver R, which is to be operated, and a circuit-controllingdevice dwhich in this case is-composed of two very thin cond ucting-platest t', placed in close proximity and very mobile, either by reason of extreme flexibility or owingto the charater of their support. To improve-their action, they should be inclosed in-a receptacle from which the air may be exhausted. The receiver R is shown as consisting of an electromagnet M, a movable armature a, aretractile spring b, and a ratchet-wheel w, provided with a spring-pawl r, which is pivot/ed to armature a, as illustrated. The apparatus being arranged as shown, it will be found that ywhen the radiations of the suuor-of any other source capable of producing the eects before described fall upon the plate P anaccumulation)v of electrical energy in the condenser C .will result. This phenomenon, I believe, is

best explained asfollows: Thesun as well as other sources of. radiant energy throw oif minnte particles of matter positively electrified, which, impinging upon the plate P, communicate an electrical charge to the same. The

opposite terminal of the condenser being connected to the ground, which may be considered as a vast reservoir of negative electricity, a feeble current ows continuously into the condenser, and inasmuch as these supposed particles are of an inconceivably small radius or curvature, and consequently charged to a relatively very high potential, this charging of the condenser may continue, as I have found in practice, almost indefinitely, even to the point of rupturing the dielectric. Obviously whatever circuit controller be employed it should operate to close the circuit in which it is included when the potential in tnde. Thus in Fig. hen the electrical-pressure at the termin s T T' rises to acertain predetermined value the plates t t', attracting each other, close the circuit connected to the terminals. This permits afiow of current which energizes the magnet M, causingit t0 draw down the armature a and impart a partial rotation to the ratchet-wheel w. As the current ceases the armature is-retracted by the spring b without, however, moving the wheel w. With the stoppage of the current the condenser has iched the desired magnif the plates t t" cease to be attracted and separate, thus restoring the circuit toits original condition.

Many useful applications of this method of utilizing the radiations emanating from the sun or other source and many ways of carrying out the same will at once suggest themselves from the above description. By way IOO yof illustration a modified arrangement is4 shown in.Fig. 2, in which the source S of radiant energy is a special form of Roentgen tube devised by me having but one terminal k, generally of aluminium, inl the form of half a sphere with a plain polished surface on the front side, from which the streams are vthrown o. It may be excited by attaching it to one of the terminals of any generator of sufficiently-high electromotive force; but whatever apparatus be used it yis important that the tubebe exhausted to a high degree, asl otherwise it might prove entirely ineffective. The working or discharge circuit connected to the terminals T T of the condenser includes in this case the primary p of a trans'- former and a circuit-controller comprising a ixed terminal or brush t and al movable terminal t' in the'shape of a wheel withconduct- :ing and insulating segments which may be rotated at an arbitrary speed by any suitable means. In inductive relation to the primary `wire or coil p is a secondary s, usually of a much` greater number of turns, tothe ends of which isconnected a receiver R. The terminals of the condenser being connected as indicated, one to an insulated plate P and the other to a grounded plate P', when the tube S is excited rays or streams of matter are'emitted from the same, which convey a positive charge to the plate P and condenser- IIO terminal T, while terminal T' is continuously receiving negative electricity from the plate Elta ingui- P'. This, as before explained, results inan accumulation of electrical energy in the con# denser, which goes on as long `as the circuit including the primary p is interrupted. Whenever the circuit is closed, owing to the rotation of the terminal t', the stored energy is discharged through the primary p, this giving rise in the secondary s to induced curr rents which operate the receiver R. xo It is clear from what has been stated above that-if the terminal T is connected to a plate supplying positive instead of negative electricity the rays' should convey negative electricity to4 plate P. VThe source S may be any r 5 form of Roentgen or Lenard tube; but it is obvious from the theory of action that in order to be very effective the electrical impulses exciting it should be wholly or at least preponderatingly of one sign. It ordinary zo symmetrical alternating currents are employed, provision should be made for allowing the rays to fallupon the plate P- only during those periods when they are productive of the desired result. Evidently if the radiations of the source be stopped or inter.

cepted or their intensityvaried in any manner, as by periodically interrupting or rythmically varying the current exciting the source, there will be corresponding changes 3o in the action upon the receiver R, and thus signals may be transmitted and many other useful eects produced. Furthermore,it will be understood that any form of circuit-closer which will respond to or be set in operation when a predetermined amount of energy is stored in the condenser may be used in lieu ofthe device specitically described with reference to Fig. l, and also that the special details of construction and arrangement of '4o. the several parts ofthe apparatus maybe very greatly varied without departure from the invention.

Having described myl invention, what I claim isV 45 1. The method of utilizing radiant energy,

which consists in charging one oi'- the armatures of a condenser by rays or radiations, and the other armature by independent-means, and discharging the condenser through a snitable receiver, as set forth. 5o

2. The method of utilizing radiant energy, which consists in simultaneously charging a condenser by means of rays or-radiations 'and an independent source of electrical enwhich consists in charging one of the armav tures of a condenser by rays or radiations and the other by independent means, varying the intensity of the said rays or radiations and periodically discharging the condenser through a suitable receiver, as set forth. 7o

5. The method of utilizing radiant energy,

`which consists in directing upon an elevated conductor, connected to one of the armatures of a condenser, rays or radiations capable of positively electrifying the same, carrying olf electricity from the other armature by connecting the same-With the ground, and dis- .charging the accumulated energy through a suitable receiver, as set forth.

6. The method of utilizing radiant energy, 8o

which consists in charging one of the armatures of a condenser by rays or radiations,and the other by independent means, and effecting by the automatic discharge of the accumulated energy the operation or control of a suitable receiver, as set forth.

i NIKOLA TESLA. Witnesses: i

M. LAWSON DYER, RICHARD DONOVAN. 

